阅读说明：本技术 一种硫酸盐微电极的制备方法 (Preparation method of sulfate microelectrode ) 是由 刘宏 刘迅 丁宁 杨留留 陈厚望 张鹏 于 2019-09-16 设计创作，主要内容包括：本发明涉及一种硫酸盐微电极的制备方法,通过采用硫酸盐离子作为载体,且溶于增塑剂中以形成均匀的溶液,得到离子载体和增塑剂中的添加剂,无缓冲离子,减少可能来自缓冲离子的干扰,与现有技术相比,本发明的有益效果如下：1、本发明可将尖端控制硫酸盐微电极的尖端直径控制在20μm之内,极大的降低了尖端的直径,不会破坏微生态环境,可实时准确获取在线的有效数据；2、本发明选用10mM K<Sub>2</Sub>SO<Sub>4</Sub>+10mM KCl为电解质的内部填充液,溶液无缓冲离子,以减少可能来自缓冲离子的干扰；本发明该硫酸盐微电极具有检测灵敏度高、输出稳定、能耗低、检测速度快、操作简单且制备成本低等优点,降低了尖端直径的同时可对微生态环境包括空气、废水及废弃物中的硫酸盐成分进行有效实时检测。(The invention relates to a preparation method of a sulfate microelectrode, which adopts sulfate ions as a carrier and dissolves in a plasticizer to form a uniform solution to obtain an ionophore and an additive in the plasticizer, has no buffer ions, and reduces the interference possibly from the buffer ions, compared with the prior art, the preparation method has the following beneficial effects: 1. the invention can control the tip diameter of the tip control sulfate microelectrode within 20 μm, greatly reduces the tip diameter, does not damage the micro-ecological environment, and can accurately acquire online effective data in real time; 2. the invention selects 10mM K 2 SO 4 +10mM KCl as an internal filling of electrolyte, the solution being free of buffer ions to reduce interference that may come from buffer ions; the sulfate microelectrode has the advantages of high detection sensitivity, stable output, low energy consumption, high detection speed, simple operation, low preparation cost and the like, reduces the diameter of the tip, and can be applied to the micro-ecological environmentThe sulfate components in the air, the waste water and the waste are effectively detected in real time.)

1. A preparation method of a sulfate microelectrode is characterized by comprising the following steps:

s1, selecting sulfate ionophore, plasticizer, additive, matrix and solvent with proper concentration;

s2, preparing a mixed solution of 1 wt% of sulfate ionophore and 1 wt% of additive in a plasticizer, adding 5 wt% of PVC into the mixed solution, dissolving in 24 hours, and finally adding about 2 volumes of THF and mixing into a liquid film;

s3, selecting K₂SO₄The solution of (4) is used as a standard solution;

s4, selecting 10mM K₂SO₄+10mM KCl solution as internal filling. Removing gas in the electrolyte by vacuumizing;

s5, immersing the silver wire in 1M HCl solution for about 1-3 minutes until its surface is covered with a smooth gray layer, the silver wire serving as an internal reference electrode;

s6, drawing the finest part of the borosilicate glass tubule tip with the outer diameter of 1.2mm to 1-2 μm by using a glass drawing instrument controlled by a program, crushing the tip of the glass tubule to the diameter of about 20 μm under a microscope by using tweezers, and then silanizing the glass tubule by immersing the tip in a silanizing agent N, N-dimethyl trimethyl silyl amine for several seconds;

s7, placing the silanized glass tubule in the S6 on a shelf in a glass dryer with a cover with the top end facing upwards, heating the glass tubule in an oven at the temperature of 150-180 ℃ for 8-10h, and cooling the glass tubule to room temperature for use after silanization;

s8, the tip of the glass capillary is immersed in the mixture for 20-30 seconds by injecting the internal electrolyte into the glass capillary from the tip using a syringe until a minute droplet is observed at the tip. Under the action of capillary force, a column of 100-400 μm is formed at the tip of the glass tubule, which can be seen under a microscope and used as a liquid film, and then the filled glass tubule is dried for 3-4 hours until THF in the liquid film is evaporated;

s9, Ag/AgCl wire was inserted into the glass capillary from its back side, and a batch of microelectrodes was placed at 10mM K at room temperature₂SO₄The solution was left for 2 to 4 hours for comparison with those of untreated microelectrodes. The microelectrode is vertically fixed on the bracket. And respectively immersing the tips of the micro-electrode and the reference micro-electrode into the standard solution of S3 to finish the preparation of the micro-electrode.

2. The method of preparing a sulfate microelectrode according to claim 1, wherein: the plasticizer in the step 1 is o-NPOE o-nitrophenyl n-octyl ether, the additive is TDDMACl tridecyl methyl ammonium chloride, the matrix is PVC, and the solvent is tetrahydrofuran.

3. The method of preparing a sulfate microelectrode according to claim 1, wherein: in step S4, it is necessary to evacuate the internal filling liquid to discharge the gas in the internal filling liquid.

4. The method of preparing a sulfate microelectrode according to claim 1, wherein: in the step S7, the temperature control speed of the oven is firstly kept constant at a constant temperature rate of 150 ℃/h for 3 hours, then is increased to 170 ℃ at a constant temperature rate of 5 ℃/h for 4 hours, and finally is increased to 180 ℃ at the same temperature increasing speed, and argon is introduced into the whole tubular furnace as a protective gas.

5. The method of preparing a sulfate microelectrode according to claim 1, wherein: in the step S5, the silver wire may be an Ag wire or an AgCl wire.

6. The method of preparing a sulfate microelectrode according to claim 1, wherein: the duration of step S6 should be controlled to be between 10-20S.

Technical Field

The invention belongs to the field of energy environment materials, and particularly relates to a preparation method of a sulfate microelectrode.

Background

The microelectrode refers to an electrode with a small working area, the limitation of the size of the electrode area is not very strict, the microelectrode comprises two meanings, ① refers to the miniaturization of the electrode, such as a miniaturized ion selective electrode which is used for directly observing the activity change of body fluid and even some important ions in cells, a glass capillary (the inner diameter of the tip is less than one millionth meter) electrode which is arranged near the surface of the cell or inserted into the cell under the control of a micromanipulator to observe the electric activity of a single cell, the microelectrode is a tool for researching cells in medicine, ② refers to a type of electrode with small electrode area but not miniaturized whole electrode in electrochemical analysis, such as an indicating electrode, a mercury drop electrode, a mercury hanging electrode, an indicating electrode in coulomb titration, a micro platinum electrode and the like which are also called as the microelectrode, the type of which has large current density due to the small electrode area and is easy to generate extremely high concentration polarization, the microelectrode has mass transfer rate, but the current sulfate microelectrode is too large of the microelectrode, can damage the ecological environment, and real-time online effective data can be obtained difficultly.

Disclosure of Invention

Aiming at the technical defects, the invention provides a preparation method of a sulfate microelectrode, the invention adopts a biological morpheme material, namely, a diaphragma juglandis, is natural, environment-friendly, cheap and easy to obtain, and adopts the following technical scheme.

In order to achieve the purpose, the invention provides the following technical scheme:

a preparation method of a sulfate microelectrode is characterized by comprising the following steps:

s1, selecting sulfate ionophore, plasticizer, additive, matrix and solvent with proper concentration;

s2, preparing a mixed solution of 1 wt% of sulfate ionophore and 1 wt% of additive in a plasticizer, adding 5 wt% of PVC into the mixed solution, dissolving in 24 hours, and finally adding about 2 volumes of THF and mixing to obtain a liquid film;

s3, selecting K₂SO₄The solution of (4) is used as a standard solution;

s4, selecting 10mMK2SO4+10 mKCl solution as the internal filling liquid. Removing gas in the electrolyte by vacuumizing;

s5, immersing the silver wire in 1M HCl solution for 1-3 minutes until the surface is covered with a smooth gray layer, wherein the silver wire is used as an internal reference electrode;

s6, withdrawing each glass micropipette from a borosilicate glass capillary inner wire with an outer diameter of 1.2mm by using a vertical pipette puller controlled by a microsensor, crushing the tip of the micropipette to a diameter of about 20 μm under a microscope using a pair of tweezers, and then silanizing the micropipette for several seconds by immersing the tip in a silanizing agent N, N-dimethyltrimethylsilylamine;

s7, placing the silanized micropipette in S6 on a shelf in a glass dryer with a cover upwards, heating the micropipette in an oven at 150-180 ℃ for 8-10h, and cooling the micropipette to room temperature for use after silanization;

s8, the tip of the micropipette is immersed in the mixture for 20-30 seconds by using a syringe to inject the internal electrolyte into the micropipette from the back of the stem until a tiny droplet is observed at the tip. Under the action of capillary force, a column of 100-400 μm is formed at the tip of the micropipette, visible under a microscope, and used as a liquid film, and then the filled micropipette is dried for 3-4 hours until THF in the liquid film is evaporated;

s9, inserting Ag/AgCl wire into the shaft from the back side, conditioning a batch of microelectrodes in 10mM K2SO4 solution for 2-4 hours at room temperature to compare with those untreated microelectrodes, vertically fixing the microelectrodes on a support, and immersing the tips of the microelectrodes and a reference microelectrode in a standard solution of S3, respectively, to complete the preparation of the microelectrodes.

Preferably, the plasticizer in the step 1 is o-NPOE o-nitrophenyl n-octyl ether, the additive is TDDMACl tridecyl methyl ammonium chloride, the matrix is PVC, and the solvent is tetrahydrofuran.

Preferably, in step S4, the internal filling liquid needs to be vacuumized to discharge the gas in the internal filling liquid.

Preferably, in step S7, the temperature control rate of the oven is first constant at a constant temperature rate of 150 ℃/h for three hours, then is increased to 170 ℃ at a constant temperature rate of 5 ℃/h for four hours, and finally is increased to 180 ℃ at the same temperature increasing rate, and argon is introduced into the whole tubular furnace as a shielding gas.

Preferably, in the step S5, the silver wire may be an Ag wire or an AgCl wire.

Preferably, the duration of step S6 should be controlled to be between 10-20S.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention can control the tip diameter of the tip control sulfate microelectrode within 20 μm, greatly reduces the tip diameter, does not damage the micro-ecological environment, and can accurately acquire online effective data in real time;

2. the invention selects 10mMK2SO4+10 mKCl as the internal filling liquid of the electrolyte, the solution has no buffer ions, SO as to reduce the interference possibly from the buffer ions;

the sulfate microelectrode has the advantages of high detection sensitivity, stable output, low energy consumption, high detection speed, simple operation, low preparation cost and the like, reduces the diameter of the tip, and can effectively detect the components in the air in real time.

Drawings

FIG. 1 is a schematic view of a liquid film sulfate microelectrode with a tiny tip.

FIG. 2 is a schematic diagram of the structure of a sulfate ionophore.

FIG. 3 is a schematic diagram of the cell assembly of the sulfate microelectrode.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.